[AlloyJay]

I work as a chemist at a project where we test for flammable gas in the headspace of containers that are to be shipped across the country.  We use GC/MS to do this.  We have recently been directed not to run any blanks or traceable control samples prior to analysis of batches of our unknown samples.  The containers are also stored in unheated buildings in subzero temperatures (today's low was -13 ^oF) and we no longer have to warm them for a predetermined period prior to testing.  Do these new requirements (or lack thereof) invalidate our analyses?

[muse]

In our lab we always run controll samples before every new analysis batch, and we run blank samples before real samples. In this way we are able to check whether impurities comes from your sample or are artefacts/impurities in the instruments.

Im not sure how the storage conditions will affect your analysis, but maybe someone else can answere that.